Vehicle brake



H. VANDERBEEK VEHICLE BRAKE Get. 30 i923.

Filed Nov. 8, 1922 3)/ 1N VEA/TOR I j y Patented Oct. 30, 1923.

Wayne and um'rlam STATES l v 1,472, PATENT'. OFFICE.

HERBER' VANDEBBEEK, 0F DETROIT, MICHIGAN, ASSIGNOB T0 THE T-DE- TBOITAXLE colPANY, 0F DETROIT, MICHIGAN, A CORPORATION 0F MCHIGAN.

l y 'vnmcmamxn .Appuoation mea number s, 1922. smal no. 599,657.

`To-aZZ whom z't may concern.'

Be it known that I, HERBERT VANnEiiBEnK,

-a citizen of the United Statesand a resif dent of the it of Detroit,Vin the county of tate of 'Michigan,. have invented a .new and usefulimprovement in Vehicle Brakes, of which'the following is aspecification. This invention relates to internal band brakes of thetoggle operated type particularly ada ted for use in connection with thewheels o motor vehicles.

One of the principal objects of the v/plesent invention is to utilizethe forces arl from the initial engagement between the brakin surfacesto increase the friction developed therebetween, thereby reducin thepower required to apply the brake. ther objects are simplicity ofconstruction, reduced cost of manufacture and compactness of design.

The invention consists principally in the novel arrangement of toggleadapted to be assisted in its operation by the tendency of the brakeband to rotate with the brake drum. The inventionl further consists inin the combinations and arparts hereinafter described the parts andrangements of and claimed.

In .the accompanying5 drawing, which forms part of this specificationand wherein likeY reference numerals refer to like arts wherever theyoccur, Fig. 1 is a 'sectional view illustrating a brake drum providedwith a toggle operated band brake embod ing my invention; Fig. 2 is adetail section view on line 2-2'of Fig. 1'.

For purposes of illustration, my invention is shown in connectionjwiththe circular brake flange 2 of a brake drum adapted to be fxedvto androtated with the driving wheel (not shown) of an automobile and isprovided with a central circular axlereceivingwpenin 4. Thisconstruction is well-known and 1t is considered unnecessary toillustrate it in detail.

'The inner surface/of the brake lian 2 is adapted tobe frictionallyengagedgeby the brake lining material 5'of a split semlflexible'metallic brake band 6. The adja. cent end portionsof the brake band areeach provided with an end .fitting 7; and the said end fittin areloosely connected by means of an el w or to gle joint comprising a pairof linksS, Wiese adjacent ends ,link 8, and the other are pivotallyconnected by means of a pivot pin 9` and whose outer ends are pivotallyconnected by means of pivot pins 10 to the respective end fittings. Thetoggle links aredisposed with their point of junction offset inwardlytoward the center of the brake drum with respect to their points ofconnection with the brake band. An actuating link 11 has a pivotalconnection at one end with the toggle links"8 at their pbint ofjunction; and, in accordance with common practice, the opposite end ofsaid actuating link is pivotally secured to the free end of a rock arm12 which is fixed to a rock shaft 13 journaled in a bracket 14 rivetedor otherwise rigidly secured to a stationary brake disk or shield 3. Therock shaft 13 is alsoprovided with the usual actuating arm 15 adapted tobe connected to the brake pedal (not shown) by means of the1` lllisualpull rod 16.

nection with the ends of the brake band, with oppositely disposedflanges 17 adapted to abut against an anchor stud 18 arrangedtherebetween which is rigidl secured to the stationary brake disk or sield 3. The abutment stud 18 is provided with oppositely extending arms19 that project across the ends of the abutment flanges 17 of the togglelinks 8 and serve to prevent sliding movement of said links on theirsupporting pivots 10. The toggleis normally held in open position bymeans of a palr of coil springs 20. One end of a spring is secured to ahook 21"formed integral wlth a toggle end of said sprin is secured to alug or ear 22 on the end fitting 7 to which said toggle link ispivotally sev cured, thereby tending to hold the toggle normally in itsbent position and the ends of the brake band clear of the drum.

' At points intermediate its ends, the brake band'is held out of contactwith the brake drum and against a plurality of stop brackets '23. bymeans of a plurality of coil springs 24. These stop brackets are ofangle section and have onel flange rigidly secured to theI stationarybrake disk 3. The other flan es of the stop brackets are shaped toconform to the curvature of the brake band which, in its contractedposition is held against said curved flanges by the springs 24. Theinner ends ofthe springs 24am toggle links 8 are provided, at points Ioffset outwardly from their points of conv lno hooked around a series ofcircumferentially spaced pins 25 that are secured to the statlonarybrake disk 3 adjacent to the central b axle receiving opening 4 therein.The outer ends of the springs that are located adjacent to the endfittmgs of the brake band are hooked into the ears or lugs 22 of Isaidend fittings; and the outer ends of the springs located adjacent to themiddle yof the brake band are hooked into holes formed in thejinwardlyprojecting lugs or ears of brackets 25 that are riveted or otherwiserigidly secured to the brake band. These springs 24, together with thesprings 20, serve to hold the brake band normally clear of the rotatingbrake drum.

' Assuming the parts to be 'in thepositions indicated in the drawing,the operation of the device is as follows:

The operator in applying the brake causes the pull rod 16 to move in thedirection of the arrow, thereby swinging the rock lever 12 in adirection that w1ll cause the toggle actuating link 11 to moveoutwardly. `This outward movement of the toggle actuating link causesthe elbow of the toggle to move outwardl away from the center of thebrake drum, w ich action tends to straighten the toggle, therebyspreading apart'the ends of the bra-ke band and forcing the same intoengagement with the inner periphery of the brake drum. When -the brakeIband 'is pressed against the rotating brake drum, the entire brakeband,by reason of its frict1onal engagement with the brake drum, will rotatewith said drum until the abutment fiange 17 of one of the toggle links 8strikes the fixed abutment s'tud 18. The action of forcing the togglelink against the abutment stud 18 'at a point offset outwardly from thecenter of the link supporting pivot 9 causes sald toggle lever to swingon said pivot 1n a direction which tends to further straighten thetoggle, thereby reducing the power -[required to apply the brake. Whenthe brake is released, the springs 20 break the toggle and draw the endsof the brake band away from the drum', the intermediate portion of theband being drawn away from the drum and against the stop brackets by thesprings 24.

The hereinbefore described arrangement admits'of considerablemodification without departing from the invention;therefore, I

do ot wish to be limited'to the precise ar,

ralggment shown and described.` l f I at I claim is: 1. A brake drum, asplit brake band yadapted to frictionally engage said drum, -a togglejolnt operatively connected to the ends of said b and for moving thesame into and out of engagement with said drum, and

1 a' statonary abutment adapted in the -en-f Wes gaged position of saidband to be engaged ortions of said toggle that are located closer to thedrum than the elbow of said toggle and its points of connection withsaid 2. A brake drum, a split brake vband adapted to frictionally engagesaid drum, a toggle joint operatively connected to the ends of said bandfor moving the 'same into and out of engagement with said drum, astationary abutment adapted in theengaged position of said band to bcengaged by portions o'f said toggle that are located closer to the drumthan the elbow of said toggle and its points of connection with saidbandi and yieldable means for normally holding said toggle clear of saidabutment.

3. A brake drum, a split brake band adapted/to frictionally engage saiddrum, aftoggle joint operatively connected to the ends of said band formoving the same into and out of engagement with said drum, a

stationary abutment adapted in the engagea position of said band to beengaged by portions of said toggle that are located closer to the drumthan the elbow of said toggle and its points of connection with saidband, and yieldable means for normally maintaining said toggle in aninoperatlve position and out of contact with said abutment.

4. A brake drum, a split brake band adapted to frictionally engage saiddrum, a toggle joint operatively connected to the ends of said Vband formoving the same into and out of engagement with said drum, a stationaryabutment adapted in the engaged position of said band to be engaged byportions of said toggle that are located closer to the drum than theelbow of said toggle and its points of connection with said band, andyieldable means connecting said toggle with the ends of said' band fornormally maintaining the toggle in an inoperative position and out ofcontact with said abutment. j

5.A brake drum, an internal brakeband adapted 'to rictionally engagesaid drum, a toggle joint operatively connected to the lends of saidband, said togglejoint being f' disposed with its elbow offset inwardlyfrom its points of connection with said band, and a xed abutment adaptedto be engaged by said toggle joint at points oset outwardly from itspoints of connection with said band. 6. A brake drum, yan internal brakeband adapted to frictionally engage said drum, a toggle jointoperatively connected to the ends of said band, said toggle joint beingdisposed with its elbow offset inwardly from its points of connectionwith s'aid band, a fixed 'abutment adapted to be engaged by said togglejoint at pointsl offset outwardlyv from its points of connection withsaid band, and lyieldable means for normally .-z-maintaining said togglein anino erative posiion and out of contact withsald abutmen -f 7. Abrake drum, a circumferentially expansible split brake band adapted whenexpanded to rictionally engage the inner surface of said drum, a togglejoint for expanding and contracting said band, said toggle jointcomprising a' pair of/links pivotally secured together and having theirends pivotally securedto the ends o\f said band, said toggle links beingdisposed with their point of junction offset inwardly from their pointsof connection with saidband, and la stationary abutment adapted in theyexpanded position of said band to be engaged by a link of said toggleat a point offset outwardly from the point of connection of said linkwith said band.

8. A brake drum, a circumferentially expansible split brake band adaptedwhen expanded to frictionally engage the inner surface of"said drum, atoggle joint-for ex'- panding and contracting said band, said togglejoint comprising a pair of links pivotally securedto the ends of saidband, said toggle links being disposed with their point of junctionoffset inwardly from their points of connection with said band, astationary abutment adapted in the expanded position of said band to beengaged by a link of said toggle at a point offset outwardly from thepoint of connection of said link with said band, and yieldable means fornormally holding said links clear of said abutment. 9. A brake drum, acircumferenti-ally expansible split brake band adapted when expanded tofrictionally engage the inner sur: face of said drum, a toggle jointforexpanding and contracting said band, said tog- 'gle joint comprising apair of links pivote ally secured together and having their endspivotally secured to the ends of said band, said toggle linksbeing'disposed with their point of junction offset inwardly from theirpoints of connection with said band, a stationary abutment adapted in,the expanded `position of said band to be engaged by alink ofsaidtoggle at a point offset outwardly from the point of connection of saidlink with said band, andyieldable means cons necting the toggle linkswith the free end portions of said band for normally maintaining saidtoggle in an inoperative position and out of contact with said abutment.

. 10. A brake drum,

a circumferentially expansible split brake band adapted when expanded toengage the inner surface of vsaidl drum, and a toggle joint forexpanding and contracting said band, said toggle comprising a pair oflinks pivotally secured together and having their ends pivotallyJsecured `to the ends of said brake band at points offset inwardly fromtheir point of connection with Said band, said links being the ends ofsaid brake disposed formed at points offset outwardly from their pointsof connection with said band with oppositely disposed abutment flanges,and a @5i stationary abutment disposed' between said abutment flangesand adapted in the expanded position of said band to be engaged'byari/abutment flange of said toggle..

11, A brake drum, a circumferentially expansible split brake bandadapted when expanded to engage the inner surface of said drum, and atoggle joint for yexpanding and contracting said band, said togglecomprising a pair of links and having their ends pivotally secured toband at points offset inwardl from their point of connection with saidband, said links beingv formed at pivotally secured together pointsoffset/outwardly from their points 8 4of connection with said band withoppositely disposed abutment flanges, a stationary abutment disposedbetween lsaid abutmentm flanges and adaptedtin the expanded position ofsaid band to be engaged by an abut- @5 ment vfiange of said toggle, andyieldable means for normally holding the abutment flanges of said toggleclear of said stationary abutment. f

127A brake drum, a circumferentiall'y ex- E@ panrsible split brake bandadapted when expanded to engage the inner surface of said drum, and atoggle joint for expanding and contracting said band, said togglecomprising a/pair of links and havin theirvends pivotally secured to theends oi?7 said brake band at points offset inwardly from their ppoint ofconnection with said band, said links being formed at points offsetoutwardly from their points of connection with said band with oppositelyabutment flanges, a stationary Yabutment'. disposed between said`abutment flanges and adapted in lthe expanded position of said band to'be engaged by an abutment flange of said toggle7 and yieldable meansfor normally maintaining I said toggle in an inoperative position withthe abutment fiange thereof out of contact with said stationaryabutment. Y

13. A brake drum, an internal brake band adapted to frictionally engagesaid drum, a toggle joint operatively connected to ythe ends of saidband, said toggle joint being pivotally secured together disposed` withits elbow offset inwardly from itspoints of connection with said band,aA fixedabutment adapted to be engaged by said toggle jloint at pointsoffset outwardly from its points of connection with said band, andyieldable means for normally

